A volcanic eruption in Iceland caused massive disruption throughout Europe in 2010. A huge ash cloud grounded more than 100,000 flights and delayed 10m passengers, costing the aviation industry more than…

Prop 91 - just one of three ballot initiatives on marijuana decriminalization
Steve Dipaola/ReutersNovember 5, 2014

Editor’s note: There were 146 state-wide ballot measures up for consideration by voters in this week’s midterm elections, covering all manner of controversial issues – from abortion and guns to minimum…

The theory that the Americas were populated by humans crossing from Siberia to Alaska across a land bridge was first proposed as far back as 1590, and has been generally accepted since the 1930s. But genetic…